Confidence intervals,significance values,maximum likelihood estimates,etc. sharpened into Occam’s razors

Abstract

Confidence sets, p values, maximum likelihood estimates, and other results of non-Bayesian statistical methods may be adjusted to favor sampling distributions that are simple compared to others in the parametric family. The adjustments are derived from a prior likelihood function previously used to adjust posterior distributions.     

美、加公共管理领域非学位教育的借鉴意义

本文就美、加高校在公共管理领域从业人员非学位教育方面的特色从培训计划、方法、师资和评估四个方面进行分析, 对其借鉴意义进行了探讨。     

this的语用综述

功能语言学和语篇学对照应的研究反映在语用学里就是指示研究。指示的研究主要集中在人称指示 ,而对方位指示 ,尤是其对this和that并没有予以足够的重视。本文结合语言学界对照应和指示的发现 ,探讨了this及其复数these作为指示和照应手段的若干方面的用法 ,如近指、文内照应、文外照应、回指、下指、具体照应、笼统照应、事物照应、概念照应、思想照应、中心词照应、修饰语照应等 ,重点放在心理近指上。     

BAYESIAN SUBSET SELECTION AND MODEL AVERAGING USING A CENTRED AND DISPERSED PRIOR FOR THE ERROR VARIANCE

This article proposes a new data‐based prior distribution for the error variance in a Gaussian linear regression model, when the model is used for Bayesian variable selection and model averaging. For a given subset of variables in the model, this prior has a mode that is an unbiased estimator of the error variance but is suitably dispersed to make it uninformative relative to the marginal likelihood. The advantage of this empirical Bayes prior for the error variance is that it is centred and dispersed sensibly and avoids the arbitrary specification of hyperparameters. The performance of the new prior is compared to that of a prior proposed previously in the literature using several simulated examples and two loss functions. For each example our paper also reports results for the model that orthogonalizes the predictor variables before performing subset selection. A real example is also investigated. The empirical results suggest that for both the simulated and real data, the performance of the estimators based on the prior proposed in our article compares favourably with that of a prior used previously in the literature.     

论林纾短篇小说的艺术创新及其缺陷

林纾短篇小说的艺术创新,一定程度上打破了清末停滞凝固的小说艺术模式,为当时的文坛注入了一股新鲜的血液.他是近代较早有意识地借鉴西方小说艺术的作家,大大拓宽了爱情小说的艺术领域.其独具特色的"技击小说"为后世的武侠小说提供了可贵的艺术经验.他的小说尽管存在着一些缺陷,但部分作品堪称文言小说的精品.     

试析高校院系资料室的隐性功能

信息时代中 ,由于网络在查找资料上的方便与快捷 ,已经对当前高校的院系资料室形成较大的冲击 ,资料室存在的合理性因此受到质疑。然而 ,笔者认为网络可以取代的只是资料室的显性功能 ,而资料室本身所具有的隐性功能则是网络所无法替代的。本文主要以资料室的隐性功能的阐释为出发点 ,认为环境与交往是资料室隐性功能发挥的重要机制 ,进而剖析高校院系资料室隐性功能的具体体现     

Bayesian analysis of elapsed times in continuous‐time Markov chains

The authors consider Bayesian analysis for continuous‐time Markov chain models based on a conditional reference prior. For such models, inference of the elapsed time between chain observations depends heavily on the rate of decay of the prior as the elapsed time increases. Moreover, improper priors on the elapsed time may lead to improper posterior distributions. In addition, an infinitesimal rate matrix also characterizes this class of models. Experts often have good prior knowledge about the parameters of this matrix. The authors show that the use of a proper prior for the rate matrix parameters together with the conditional reference prior for the elapsed time yields a proper posterior distribution. The authors also demonstrate that, when compared to analyses based on priors previously proposed in the literature, a Bayesian analysis on the elapsed time based on the conditional reference prior possesses better frequentist properties. The type of prior thus represents a better default prior choice for estimation software.     

资料室在制作网络课件中的作用

巩固和发展多种媒体网络教学,积极发展计算机信息技术教育及辅助教学,推动电脑多媒体技术和计算机网络技术在学校教学中的应用。本文探讨了网络课件在教学改革中的重要性和它在教学中的应用以及资料室在制作网络课件过程中的作用。     

The empirical Bayes estimators of the parameter of the Poisson distribution with a conjugate gamma prior under Stein's loss function

For the hierarchical Poisson and gamma model, we calculate the Bayes posterior estimator of the parameter of the Poisson distribution under Stein's loss function which penalizes gross overestimation and gross underestimation equally and the corresponding Posterior Expected Stein's Loss (PESL). We also obtain the Bayes posterior estimator of the parameter under the squared error loss and the corresponding PESL. Moreover, we obtain the empirical Bayes estimators of the parameter of the Poisson distribution with a conjugate gamma prior by two methods. In numerical simulations, we have illustrated: The two inequalities of the Bayes posterior estimators and the PESLs; the moment estimators and the Maximum Likelihood Estimators (MLEs) are consistent estimators of the hyperparameters; the goodness-of-fit of the model to the simulated data. The numerical results indicate that the MLEs are better than the moment estimators when estimating the hyperparameters. Finally, we exploit the attendance data on 314 high school juniors from two urban high schools to illustrate our theoretical studies.     

Nonparametric Bayesian inference for multivariate density functions using Feller priors

Multivariate density estimation plays an important role in investigating the mechanism of high-dimensional data. This article describes a nonparametric Bayesian approach to the estimation of multivariate densities. A general procedure is proposed for constructing Feller priors for multivariate densities and their theoretical properties as nonparametric priors are established. A blocked Gibbs sampling algorithm is devised to sample from the posterior of the multivariate density. A simulation study is conducted to evaluate the performance of the procedure.